std::perror
std::perror
Defined in header <cstdio> | ||
---|---|---|
void perror( const char *s ); |
Prints a textual description of the error code currently stored in the system variable errno
to stderr
.
The description is formed by concatenating the following components:
- the contents of the null-terminated byte string pointed to by
s
(unlesss
is a null pointer) -
": "
- implementation-defined error message describing the error code stored in
errno
. This message is identical to the output ofstd::strerror(errno)
. -
'\n'
.
Parameters
s | - | pointer to a null-terminated string with explanatory message |
Return value
(none).
Example
#include <cmath> #include <cerrno> #include <cstdio> int main() { double not_a_number = std::log(-1.0); if (errno == EDOM) { std::perror("log(-1) failed"); } }
Output:
log(-1) failed: Numerical argument out of domain
See also
macro which expands to POSIX-compatible thread-local error number variable (macro variable) |
|
returns a text version of a given error code (function) |
|
C documentation for perror |
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